本研究利用流體引導之反溶劑蒸氣輔助結晶法法製作出三碘化甲胺鉛(CH3NH3PbI3)奈米線，並透過將苯乙基碘化銨[Phenethylammonium iodide(PEAI)]加入CH3NH3PbI3溶液中或將溶劑由二甲基甲醯胺(DMF)混摻入γ-丁内酯(GBL)的方式來延緩CH3NH3PbI3結晶時間，延緩結晶時間程度不同得到線型和塊狀兩種不同的CH3NH3PbI3結晶形貌，並且將線型結晶應用於光感測元件上。本文利用原子力顯微鏡、掃描式電子顯微鏡、光學顯微鏡觀察不同製程下的CH3NH3PbI3奈米線，發現結晶速度變慢時會出現更密集尺度更小的奈米線，而延緩結晶速度再更慢時可以看到結晶型態由線狀變為方形，並且減緩結晶速度會使奈米線更接近單晶，透過傅立葉轉換紅外線光譜儀、光致螢光光譜、低掠角X光繞射儀探討奈米線的材料特性，得知不同製程參數並不會影響CH3NH3PbI3鈣鈦礦的結晶結構，並且激子在延緩結晶時間後的奈米線中有較長的生命週期。
將CH3NH3PbI3奈米線應用在光感測器上，在光導體元件中量測不同波長雷射光照射下的電性，得知藍光照射時，元件有最大光響應，而紅、綠光照射時，元件光響應較小，並且延緩結晶時間可以得到響應率較好的光導體元件，接著透過導電式原子力顯微鏡分析不同製程參數CH3NH3PbI3結晶的光電流，其中方形結晶表現出了超乎預期的性能。
本研究解析CH3NH3PbI3奈米線的結構及光電特性，成功解析減緩結晶時間對CH3NH3PbI3形貌造成的影響，並以減緩結晶時間方法製造出接近單晶的奈米線，再藉由改良後的奈米線製作出性能更優異的光偵測器元件，光電流甚至可以達到改良前元件的30倍。

In this study, a fluid-guided, antisolvent, vapor-assisted crystallization method was used to fabricate CH3NH3PbI3 nanowires. Adding phenethylammonium iodide (PEAI) or γ-butyrolactone (GBL) to the CH3NH3PbI3 precursor solution slowed down the crystallization time of CH3NH3PbI3, whose crystallinity could be increased.
The morphology of the CH3NH3PbI3 crystals were analyzed using an atomic force microscope (AFM) and scanning electron microscope. The size of CH3NH3PbI3 nanowires was smaller than those fabricated without the addition of PEAI or GBL. As an excessive proportion of PEAI or GBL was added, the crystalline form of CH3NH3PbI3 changed from wire to square shaped. Time-resolved photoluminescence analysis reveals that excitons have a longer lifetime in the CH3NH3PbI3 crystals that were grown by slow crystallization compared with that by fast crystallization. Conductive AFM was applied to measure the photocurrents of various CH3NH3PbI3 crystals; among them, square-shaped crystals showed the best performance. The photoconductors were prepared on the basis of the produced CH3NH3PbI3 nanowires to detect different wavelengths of light. We analyzed the effect of extending crystallization time on the preparation of CH3NH3PbI3 nanowires and deeply investigated their crystalline structure and photoelectrical properties. The CH3NH3PbI3 nanowires with improved crystallinity were successfully fabricated and applied to photosensors with excellent performance.

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